This invention deals with an improved construction and method of positioning a plurality of socket terminals on an electrical circuit board such as a printed circuit board having a plurality of openings into which the pin portions of the socket terminals can be hand assembled upon the circuit board in the desired position, such involves undue time consumption; and, accordingly, it is generally accepted practice to utilize socket terminal carrier assemblies for group insertion into the printed circuit board.
Such carrier assemblies are conventionally in the form of an aluminum plate having a plurality of downwardly extending thin fingers for entrance into the open sleeve portion of the socket terminals such that the terminals are held thereby and inserted into the PC board as a group in the desired array. Such system has found wide acceptance for socket terminals destined for single in-line and dual in-line positioning on circuit boards but are not particularly adapted with the recently introduced more complex pin grid arrays associated with electronic circuitry, i.e., integrated circuits. Thus it would be unwieldy to produce a conventional aluminum carrier having downwardly extending fingers in the desired number and geometric configuration necessary to group insert the number of socket terminals associated with such integrated circuit pin grid arrays. Accordingly, it would be desirable to be able to simply and effectively group position socket terminals in both simple and complex pin arrays by the same means.
Another problem associated with the use of presently utilized conventional socket terminal carrier assemblies such as the above-described aluminum plates is that there is both considerable tooling cost and lead time required to produce such carriers. Accordingly, a further desirable feature would be the provision of a means by which both lead time and tooling cost could be substantially reduced.
Still another problem associated with the use of aluminum carriers as above-described is that the slender fingers which are inserted into the lead socket can sometimes undesirably alter the electrical conductive properties of the sleeve portion of such sockets as by scratching or otherwise damaging the internal surface thereof. Such sleeves are very often provided with a very thin gold plate for contact of the pins of the active electrical or electronic circuit element and, accordingly, can be fragile and unnecessary contact therewith should be avoided. Also as when such aluminum carriers are carelessly removed, it is possible to actually pull out the contact sleeve of one or more sockets thus rendering the device useless. Accordingly, a further object of the present invention is the provision of a system and means whereby internal portions of the lead sockets are not contacted during the group insertion thereof into the printed circuit board.
It is also important that inspection of the soldered connections, particularly the connections between the upper portion of the printed board and the downwardly extending lead socket pin, not be obscured or otherwise hindered from proper inspection prior to the removal of the carrier element. Accordingly, a further object of the present invention is the provision of an improved system and means for group insertion of lead sockets which do not hinder solder inspection.
The above objectives as well as other objectives as will hereinafter be more apparent are achieved in the present invention by the provision of a construction for temporarily positioning a plurality of socket terminals on an electrical circuit board in a predetermined configuration prior to solder connection thereto, comprising a sheet of relatively thin, flexible, electrically insulative, resinous plastic material having a plurality of holes extending therethrough, said holes arranged in a planar configuration about said sheet to correspond with said predetermined positioning of said socket terminals in said circuit board, a plurality of socket terminals each having a pin adapted for insertion into an opening in said board at their lower end and an enlarged generally cylindrical head at their upper end, said enlarged head having upper and lower sections defined by an inwardly extending perimetal groove intermediate the height thereof and of a lateral extend less said upper and lower sections, said holes of a perimetal extent less than said head sections but generally corresponding to or slightly greater than that of said groove, said terminals adapted for positioning upon said sheet with the heads thereof extending through said holes and the sheet extending into said grooves and therein the leading edge of at least one of said upper and lower head sections is provided with a longitudinally oriented, sheet contacting surface to enable said terminals to be pushed positioned into said grooves.
Other objects, features and advantages of thhe invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawings.